If “Tommy” is the Who’s great rock opera, its successor, “Quadrophenia,” might more accurately be described as the rock group’s great opera.

That perspective is reinforced by “Pete Townshend’s Classic Quadrophenia,” which the Who’s lead guitarist and chief songwriter brought to the Greek Theatre on Saturday with the backing of a massive orchestra and choir and featured soloists Billy Idol, classically trained English tenor Alfie Boe, and Townshend himself.

It was the last of just four (fittingly) U.S. performances of the orchestral adaptation of the Who’s original work that Townshend commissioned from his wife, composer Rachel Fuller, “so that when I died, there would be something I had approved that could be played by fans other than rock fans listening to the original recording,” he told The Times in June.

But beyond merely creating something for posterity, “Classic Quadrophenia” was given its live premiere in London in 2015, was documented that year on a recording released by the classical label Deustche Grammophon and extended its life with the recent quartet of shows in the U.S.

This meeting of rock and classical traditions proved a good fit on Saturday, the overriding impression being one of the joy those on both sides of the fence derived from working a bit outside their customary boxes.

That was evident in the broad smiles throughout the evening on the faces of 76 orchestra musicians and more than 80 members of a choir. It was equally apparent in the coiled-spring energy exhibited by Boe, who carried the bulk of the singing duties, and the rock star power delivered by Townshend and Idol in their supporting roles.

The Who were essentially rock’s original punks, and Townshend was more likely to snarl than court anyone’s affection. His angry outsider attitude is central to “Quadrophenia,” perhaps his most autobiographical work.

It’s the story of a young mod named Jimmy searching for identity and acceptance on the gritty streets of England in the mid-’60s. Even more than “Tommy,” “Quadrophenia” at its core is closer to opera, beginning with the four central musical themes on which Townshend built it.

Originally the idea was that each theme represented one member of the Who: Lead singer Roger Daltrey embodied the alienation in “Helpless Dancer,” wild man drummer Keith Moon was the gnarly “Bellboy,” bassist John “The Ox” Entwistle was reflected in the yearning “Is It Me?” and Townshend envisioned the transcendent “Love Reign O’er Me” for himself.

“Classic Quadrophenia” doesn’t serve those up in direct linear fashion, but does allow various guises to be played out as the work proceeds. Boe brought plenty of vocal firepower to the songs originally sung by Daltrey, one of rock’s greatest belters.

His classical training was apparent both in his stamina over the course of the two-hour work, and in the control and focus he brought to the songs, even if his polished tenor is slightly thinner and less raw than Daltrey’s full-throated bellow.

Idol contributed the signature sneer and fist thrust he perfected 40 years ago fronting London punk band Generation X and has played on in the four decades since. He joined Boe in the mini-opera-within-the-opera, “The Punk Meets the Godfather,” while Townshend seemed to fully enjoy himself invoking characters such as the bus driver in “The Dirty Jobs.”

The orchestra and choir, led by Robert Ziegler, brought to life the expansive musical textures Townshend originally imitated with electronic synthesizers, adding colors that enhance the myriad emotions Townshend is exploring: fear, insecurity, false bravado, loneliness and the spirit of freedom mixed with uncertainty at the onset of adulthood.

If this rendition sacrifices some of the sonic punch that the Who packed into the recording, and subsequent live performances of the songs, the consolation is the orchestral grandeur that replaces it. When Boe reaches the climactic reading of “Love Reign O’er Me,” he and the orchestra bring the work to a thrillingly powerful conclusion.

That also set up a conundrum for an encore-hungry rock audience, as it is a tough act to follow. The solution? Townshend, Boe and Idol returned for the only number all three joined in on all night, a reprise of “Quadrophenia’s” opening number, “The Real Me.”

The sight of Boe, who is 43, Idol (61) and Townshend (72) bounding like teenagers across the stage in front of more than 150 singers and instrumentalists in formal wear made it tough for even the most hardened punk to suppress a smile.

There also was a good cause element to the performance: Part of the proceeds benefit Teen Cancer America.

CAPTION

Justin Chang and Glenn Whipp talk about the top contenders of the awards season, including "Call Me by Your Name" and "The Florida Project."

Justin Chang and Glenn Whipp talk about the top contenders of the awards season, including "Call Me by Your Name" and "The Florida Project."

CAPTION

Justin Chang and Glenn Whipp talk about the top contenders of the awards season, including "Call Me by Your Name" and "The Florida Project."

Justin Chang and Glenn Whipp talk about the top contenders of the awards season, including "Call Me by Your Name" and "The Florida Project."

CAPTION

Justin Chang and Glenn Whipp on what critics awards mean for the Oscars, factoring in the academy's expanding membership.

Justin Chang and Glenn Whipp on what critics awards mean for the Oscars, factoring in the academy's expanding membership.

CAPTION

Two men return home from World War II to work on a farm, where they struggle to deal with racism and adjusting to life after war in "Mudbound." Video by Jason H. Neubert

Two men return home from World War II to work on a farm, where they struggle to deal with racism and adjusting to life after war in "Mudbound." Video by Jason H. Neubert

CAPTION

It's quite the challenge trying to interview the energetic child stars of "The Florida Project."

It's quite the challenge trying to interview the energetic child stars of "The Florida Project."

CAPTION

Director Dee Rees talks about casting Mary J. Blige, Carey Mulligan and Jason Mitchell for her film "Mudbound." After loving Mitchell's performance in "Straight Outta Compton," Rees said, "I'd be so lucky to get him in my film."

Director Dee Rees talks about casting Mary J. Blige, Carey Mulligan and Jason Mitchell for her film "Mudbound." After loving Mitchell's performance in "Straight Outta Compton," Rees said, "I'd be so lucky to get him in my film."

Michelle Shiers

Billy Idol, left, and Alfie Boe play off one another during "Pete Townshend's Classic Quadrophenia" at the Greek Theatre in Los Angeles on Saturday, Sept. 16.

Billy Idol, left, and Alfie Boe play off one another during "Pete Townshend's Classic Quadrophenia" at the Greek Theatre in Los Angeles on Saturday, Sept. 16. (Michelle Shiers)